A strong earthquake has shaken southern Ecuador and northern Peru, killing at least 14 people, trapping others under rubble and littering streets with debris and fallen power lines.

The US Geological Survey reported an earthquake with a magnitude of about 6.8 that was centred just off the Pacific coast, about 80 kilometres south of Guayaquil, Ecuador's second-largest city.

One of the victims died in Peru, while 13 others died in Ecuador, where authorities also reported that at least 126 people were injured.

Ecuadorian President Guillermo Lasso told reporters the earthquake had "without a doubt … generated alarm in the population".

Mr Lasso's office in a statement said 11 of the victims died in the coastal state of El Oro and two in the highlands state of Azuay.

In Peru, the earthquake was felt from its northern border with Ecuador to the central Pacific coast.

Peruvian Prime Minister Alberto Otárola said a four-year-old girl died from head trauma she suffered in the collapse of her home in the Tumbes region, on the border with Ecuador.

One of the victims in Azuay was a passenger in a vehicle crushed by rubble from a house in the Andean community of Cuenca, according to the Risk Management Secretariat, Ecuador's emergency response agency.

In El Oro, the agency also reported that several people were trapped under rubble.

In the community of Machala, a two-story home collapsed before people could evacuate, a pier gave way and a building's walls cracked, trapping an unknown number of people.

The agency said firefighters worked to rescue people while the National Police assessed damage, their work made more difficult by downed lines that interrupted telephone and electricity service.

'We all ran out into the streets'

The presidency's communication agency said at least seven homes were destroyed, while 50 more were damaged.

Around 20 educational buildings and more than 30 health centres were also affected and multiple roadways were blocked by landslides caused by the earthquake.

"We all ran out into the streets ... we were very scared," said Ernesto Alvarado, a resident of Isla Puna near the epicentre, adding that some homes had collapsed.

Machala resident Fabricio Cruz said he was in his third-floor apartment when he felt a strong tremor and saw his television hit the ground. He immediately headed out.

He added that when he looked around, he noticed the collapsed roofs of nearby houses.

Ecuador's government also reported damages to health care centres and schools. Lasso said he would travel on Saturday to El Oro.

In Guayaquil, about 270 kilometres south-west of the capital, Quito, authorities reported cracks in buildings and homes, as well as some collapsed walls.

Authorities ordered the closure of three vehicular tunnels in Guayaquil, which anchors a metro area of over 3 million people.

Videos shared on social media show people gathered on the streets of Guayaquil and nearby communities. People reported objects falling inside their homes.

One video posted online showed three anchors of a show dart from their studio desk as the set shook.

They initially tried to shake it off as a minor quake but soon fled off camera. One anchor indicated the show would go on a commercial break, while another repeated, "My God, my God."

A report from Ecuador's Adverse Events Monitoring Directorate ruled out a tsunami threat.

Peruvian authorities said the old walls of an Army barracks collapsed in Tumbes.

Ecuador is particularly prone to earthquakes. In 2016, a quake centred farther north on the Pacific Coast in a more sparsely populated area of the country killed more than 600 people.

ABC/wires